/**
* Determine if current rule is relevant based on an action and resource
*
* @param string|array $action Action in question
* @param string|mixed $resource Name of resource or instance of object
* @return boolean
*/
public function isRelevant($action, $resource)
{
// Nested resources can be passed through a associative array, this way conditions which are
// dependent upon the association will work when using a class.
$resource = is_array($resource) ? head(array_keys($resource)) : $resource;
return parent::isRelevant($action, $resource);
}